Method for recycling thermal insulation material, recycled article and refrigerator

ABSTRACT

Refrigerators containing vacuum insulation material which has glass fiber assembly as the core material and rigid urethane foam are pulverized separately from refrigerators not containing vacuum insulation material, and the waste thermal insulation materials discharged from these types of refrigerators are stored in different recovery towers for waste thermal insulation materials. In an inorganic material content adjusting process, appropriate amounts are fed from the respective recovery towers into a mixer so as to prepare mixed waste materials whose inorganic material content has been adjusted. In the subsequent waste material processing process, the mixed waste materials with an adjusted percentage of inorganic material content are subjected to an appropriate powdering operation, and the resulting powder is sealed into a packaging member under a reduced pressure so as to obtain vacuum insulation material.

TECHNICAL FIELD

The present invention relates to a method for recycling thermalinsulation material containing rigid urethane foam and vacuum insulationmaterial which has inorganic material as the core material, and alsorelates to a recycled article and a refrigerator.

BACKGROUND ART

In recent years, in terms of environmental protection, the recycling ofwaste household electric appliances such as refrigerators and TV setshas been an extremely important issue, and various measures have beentaken for this purpose.

In addition, from the importance of prevention of global warming, whichis a global environment issue, energy conservation is consideredessential and has also been pursued towards consumer-oriented products.Under such circumstances, a particularly remarkable improvement inperformance is observed in foam insulation materials such as rigidurethane foam used in refrigerators, freezers, showcases and the like,while vacuum insulation materials and high-performing thermal insulatedboxes utilizing these materials have been heavily developed.Furthermore, various measures have been taken for the recycling of thesematerials.

For example, Japanese Patent Laid-Open Application No. 2001-183054suggests an approach to recycling foamed urethane used as the thermalinsulation material in refrigerators; in this approach, regeneratedpolyol is used as a component of urethane raw solution. Japanese PatentLaid-Open Application No. H10-310663 suggests an approach to decomposingand recycling polyurethane resin; in this approach, polyurethane resinis chemically decomposed by using water in a supercritical orsubcritical state, thus recovering raw material compounds and utilizableraw material derivatives of polyurethane resin.

However, so far, no consideration has been taken of the recycling ofrigid urethane foam and vacuum insulation material used together, andthey have probably been buried as mixed waste materials, without beingrecycled. With an expectation of increasing application of vacuuminsulation material in the future to achieve higher insulation, it isextremely important to think about effective recycling.

When used in a thermal insulated box like a refrigerator, vacuuminsulation material is generally used with rigid urethane foam. However,the vacuum insulation material comes into intimate contact with thehighly adhesive urethane foam, thus making it extremely difficult toseparate the vacuum insulation material only. This results in disposingboth materials without separating them from each other. Such mixed wastematerials containing different kinds of materials do not have a uniformquality, so that if they are used for recycled products, the recycledproducts do not have a uniform quality, and are not suitable forindustrial products.

For industrial recycling, it is most important that mixed wastematerials have a uniform quality.

SUMMARY OF THE INVENTION

In view of the aforementioned problems, the present invention has anobject of contributing to the recycling of thermal insulation materialcontaining rigid urethane foam and vacuum insulation material. In orderto achieve the object, the present invention provides a method forrecycling thermal insulation material in such a manner that mixed wastematerials can have a uniform quality and be reused at high quality, andalso provides a recycled article. The present invention also provides arefrigerator that enables mixed waste materials to have a uniformquality and to be reused at high quality in order to contribute to therecycling of thermal insulation material containing rigid urethane foamand vacuum insulation material, and also to contribute to an improvementin the rate of recycling of waste refrigerators.

In order to achieve the aforementioned objects, the method for recyclingthermal insulation material according to the present invention at leastincludes an inorganic material content adjusting process for adjustingthe percentage of inorganic material content in mixed materialscontaining rigid urethane foam and inorganic material, thus making thequality of the mixed materials uniform. As a result, waste thermalinsulation materials containing rigid urethane foam and vacuuminsulation material which has inorganic material as the core materialcan be reused at high quality.

A recycled article according to the present invention is made from wastethermal insulation materials containing rigid urethane foam and vacuuminsulation material which has inorganic material as the core material.The recycled article is characterized by undergoing at least aninorganic material content adjusting process for adjusting thepercentage of inorganic material content in mixed materials containingrigid urethane foam and inorganic material, thus making the quality ofthe mixed materials uniform. As a result, the waste thermal insulationmaterials containing rigid urethane foam and vacuum insulation materialwhich has inorganic material as the core material can be reused at highquality. The refrigerator according to the present invention is providedwith vacuum insulation material which has inorganic material as the corematerial and with rigid urethane foam, and the refrigerator ischaracterized by having a means for indicating the use of the vacuuminsulation material in the refrigerator. With this characteristic, therefrigerator can be subjected to an appropriate recycling procedureindented for refrigerators containing vacuum insulation material.

As a result, waste thermal insulation materials containing vacuuminsulation material which has inorganic material as the core materialcan be reused as the recycled article of high quality.

BRIEF DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is a flowchart depicting a first embodiment of the recyclingmethod according to the present invention.

FIG. 2 is a flowchart depicting a second embodiment of the recyclingmethod according to the present invention.

FIG. 3 is a flowchart depicting a third embodiment of the recyclingmethod according to the present invention.

FIG. 4 is a flowchart depicting a fourth embodiment of the recyclingmethod according to the present invention.

FIG. 5 is a flowchart depicting a fifth embodiment of the recyclingmethod according to the present invention.

FIG. 6 is a flowchart depicting a sixth embodiment of the recyclingmethod according to the present invention.

FIG. 7 is a cross sectional view of a particle board in a seventhembodiment of a recycled article according to the present invention.

FIG. 8 is a view of vacuum insulation material in an eighth embodimentof the recycled article according to the present invention.

FIG. 9 is a cross sectional view of a particle board in a ninthembodiment of the recycled article according to the present invention.

FIG. 10 is a cross sectional view of vacuum insulation material in atenth embodiment of the recycled article according to the presentinvention.

FIG. 11 is a schematic view of an eleventh embodiment of a refrigeratoraccording to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is characterized in that the recycling procedurefor thermal insulation material containing rigid urethane foam andvacuum insulation material which has inorganic material as the corematerial at least includes an inorganic material content adjustingprocess for adjusting the percentage of inorganic material content inmixed waste materials containing rigid urethane foam and inorganicmaterial. The present invention provides a method for recycling thermalinsulation material in such a manner that mixed waste materialscontaining rigid urethane foam and inorganic material can have a uniformquality and be reused as high quality materials, and also provides arecycled article and a refrigerator. The present invention can thusfacilitate to make the mixed waste materials containing rigid urethanefoam and inorganic material have a uniform quality and be reused as highquality materials.

The embodiments of the present invention will be described in detail asfollows with reference to FIGS. 1 to 10. The present invention, however,is not limited to these embodiments.

First Exemplary Embodiment

FIG. 1 is a flowchart depicting a method for recycling refrigerators anda method for producing a particle board as a recycled article accordingto a first embodiment.

The procedural steps will be described with reference to FIG. 1. In FIG.1, waste refrigerators which have been carried to a waste-treatmentfacility first undergo discriminating process 1 so as to be divided, inaccordance with the indications on the outer boxes of the refrigerators,into refrigerators containing vacuum insulation material which hasinorganic material as the core material and rigid urethane foam(hereinafter referred to as the multi thermal insulation material typerefrigerators), and refrigerators containing rigid urethane foam, butnot vacuum insulation material (hereinafter referred to as the singlethermal insulation material type refrigerators).

Next, the multi thermal insulation material type refrigerators and thesingle thermal insulation material type refrigerators undergo removingprocess 2 for removing valuables such as compressors and refrigerants inthe freezers, and then proceed to pulverizing process 3 where sortingoperation 4 is performed. In sorting operation 4, pulverized wastematerials are sorted into predetermined kinds of materials by usingmagnetic force, wind force or other means so as to be recovered. Thewaste thermal insulation materials sorted in this process undergofoaming gas recovering process 5 where foaming gas contained in therigid urethane foam is recovered.

The multi thermal insulation material type refrigerators and the singlethermal insulation material type refrigerators can take turns in usingthe facilities for pulverizing process 3, sorting operation process 4and foaming gas recovering process 5. When the single thermal insulationmaterial type refrigerators are treated after the multi thermalinsulation material type refrigerators are treated, it is preferable toclean inside the facilities for these processes in order to removeinorganic material remaining in the facilities.

After the recovery of the foaming gas, the waste thermal insulationmaterials which have been discharged from the multi thermal insulationmaterial type refrigerators and single thermal insulation material typerefrigerators are stored respectively in different recovery towers 61and 62 for waste thermal insulation materials. In recovery tower 61 withthe waste thermal insulation materials recovered from the multi thermalinsulation material type refrigerators, the percentage of inorganicmaterial content in the waste materials is measured to use theinformation when the waste thermal insulation materials are mixed withthe waste thermal insulation materials recovered from the single thermalinsulation material type refrigerators in the subsequent inorganicmaterial content adjusting process 7.

In inorganic material content adjusting process 7, based on themeasurement results of the percentage of inorganic material content,appropriate amounts are fed from the respective recovery towers 61 and62 into mixer 8 so as to prepare mixed waste materials whose inorganicmaterial content has been adjusted. The inorganic material content hereis not less than 0.01% nor more than 99.99%, and is adjusted inaccordance with the required physical properties of the recycledarticle. In the first embodiment, the appropriate percentage ofinorganic material content is not less than 0.01% nor more than 10%, andmore preferably, not less than 0.01% nor more than 2%. When the particleboard needs to have high bending strength, it is preferable that thepercentage of inorganic material content is low.

In the subsequent waste material processing process 9, the mixed wastematerials whose inorganic material content has been adjusted aresubjected to an appropriate grain size adjustment in grain sizeadjusting process 10. After being subjected to mixing process 11 forbeing mixed with timber chips and binder, and pressure molding process12, the mixed waste materials are formed into particle board 13. Here,the mixture with the timber chips and binder is optional, and theamounts to be added are not restricted.

The particle board is thus formed by pressurizing the mixed wastematerials whose inorganic material content has been adjusted and whichcontain rigid urethane foam and inorganic material, so that it can havestrength as a board member. In this manner, thermal insulation materialscontaining rigid urethane foam and vacuum insulation material which hasinorganic material as the core material can be reused as high qualitymaterials.

Second Exemplary Embodiment

FIG. 2 is a flowchart depicting a method for recycling refrigerators anda method for producing vacuum insulation material as a recycled articleaccording to a first embodiment.

The procedural steps will be described with reference to FIG. 2. In FIG.2, waste refrigerators which have been carried to a waste-treatmentfacility first undergo discriminating process 1 so as to be divided, inaccordance with the indications on the outer boxes of the refrigerators,into multi thermal insulation material type refrigerators with a glassfiber assembly as the core material, and single thermal insulationmaterial type refrigerators.

Next, valuables such as compressors and refrigerants in the freezers areremoved from the multi thermal insulation material type and singlethermal insulation material type refrigerators, and then the remainingwaste materials are sorted into predetermined kinds of materials so asto be recovered. Then, foaming gas contained in the rigid urethane foamin the sorted thermal insulation materials is recovered in foaming gasrecovering process 5.

After the recovery of the foaming gas, the waste thermal insulationmaterials which have been discharged from the multi thermal insulationmaterial type and single thermal insulation material type refrigeratorsare stored respectively in different recovery towers 61 and 62 for wastethermal insulation materials. In recovery tower 61 with the wastethermal insulation materials recovered from the multi thermal insulationmaterial type refrigerators, the percentage of inorganic materialcontent in the waste materials is measured to use the information whenthe waste thermal insulation materials are mixed with the waste thermalinsulation materials recovered from the single thermal insulationmaterial type refrigerators in the subsequent inorganic material contentadjusting process.

In inorganic material content adjusting process 7, based on themeasurement results of the percentage of inorganic material content,appropriate amounts are fed from the respective recovery towers 61 and62 into mixer 8 so as to prepare mixed waste materials whose inorganicmaterial content has been adjusted. The inorganic material content hereis not less than 0.01% nor more than 99.99%, and is adjusted inaccordance with the required physical properties of the recycledarticle. In the second embodiment, the appropriate percentage ofinorganic material content is not less than 0.1% nor more than 60%, andmore preferably, not less than 0.5% nor more than 40%. When reused asthe core material of vacuum insulation material, the inorganic materialfunctions as an modifier for the filling performance of waste rigidurethane foam, so that the optimum amount to be added is determined bythe size of the surface area of the rigid urethane foam powder.

In the subsequent waste material processing process 9, the mixed wastematerials whose inorganic material content has been adjusted aresubjected to an appropriate powdering operation in the next process 14.Then in sealing process 15, the waste powder is sealed into a packagingmember under a reduced pressure so as to obtain vacuum insulationmaterial 16.

In the second embodiment, the mixed waste materials containing rigidurethane foam and glass fiber assemblies have an appropriate percentageof glass fiber assembly content and are finely powered, thus improvingthe filling performance of the rigid urethane foam in the form of a finepowder. As a result, in the vacuum insulation material thus produced,the pores formed by the rigid urethane foam powder have a minimized sizeeven if the porosity is the same as the conventional one, so as to havehigh insulation properties. This makes it possible to reuse thermalinsulation material containing rigid urethane foam and vacuum insulationmaterial which has inorganic material as the core material as highquality material.

Third Exemplary Embodiment

FIG. 3 is a flowchart depicting a method for recycling refrigeratorscontaining rigid urethane foam and vacuum insulation material which hasinorganic material as the core material (the multi thermal insulationmaterial type refrigerators), and a method for producing a particleboard as a recycled article according to a third embodiment.

The procedural steps will be described with reference to FIG. 3.

Waste refrigerators which have been carried to a waste-treatmentfacility first undergo discriminating process 1 so as to be divided, inaccordance with the indications on the outer boxes of the refrigerators,into the multi thermal insulation material type refrigerators and singlethermal insulation material type refrigerators. The term “single thermalinsulation material type refrigerators” indicate refrigerators whichhave only rigid urethane foam as the thermal insulation material.

Next, the multi thermal insulation material type refrigerators undergoremoving process 2 for removing valuables such as compressors andrefrigerants in the freezers, and then proceed to separating process 17where the rigid urethane foam and the vacuum insulation material are cutout as integral units. Separating process 17 prevents the integral unitsfrom being pulverized together with other units, thus making the sortingoperation either unnecessary or very simple.

After the integral units of the waste thermal insulation materialsundergo grinding operation 18, foaming gas contained in the thermalinsulation materials is recovered in recovering process 5. The grindingoperation is not the only approach available for the recovery of thefoaming gas.

After the recovery of the foaming gas, the mixed waste materialscontaining rigid urethane foam and inorganic material which have beendischarged from the multi thermal insulation material type refrigeratorsare stored in recovery tower 61 for waste thermal insulation materials.The percentage of inorganic material content in the waste materialswhich is measured in this process is used in the subsequent inorganicmaterial content adjusting process.

In inorganic material content adjusting process 7, inorganic material issorted out by air sorter 19 by making use of the difference in specificgravity between the rigid urethane foam and the inorganic material. Theoperating conditions of air sorter 19 are determined based on themeasurement results of the percentage of inorganic material content inthe previous process 7. As the result of this operation, mixed wastematerials whose inorganic material content has been adjusted areobtained. The inorganic material content here is not less than 0.01% normore than 99.99%, and is adjusted in accordance with the requiredphysical properties of the recycled article. In the third embodiment,the appropriate percentage of inorganic material content is not lessthan 0.01% nor more than 10%, and more preferably, not less than 0.01%nor more than 2%. When the particle board needs to have high bendingstrength, it is preferable that the percentage of inorganic materialcontent is low.

In the subsequent waste material processing process 9, the mixed wastematerials whose inorganic material content has been adjusted aresubjected to an appropriate grain size adjustment (grain size adjustingprocess 10) depending on their uses. After being subjected to mixingprocess 11 for being mixed with timber chips and binder, and pressuremolding process 12, the mixed waste materials are formed into particleboard 13.

Since being produced by pressurizing the mixed waste materials whoseinorganic material content has been adjusted and which contain rigidurethane foam and inorganic material, the particle board can havestrength as a board member. In this manner, thermal insulation materialscontaining rigid urethane foam and vacuum insulation material which hasinorganic material as the core material can be reused at high quality.

Since the adjustment of the percentage of inorganic material content isdone by removing some amount of the inorganic material, it is of coursepossible to reduce the percentage of inorganic material content, or evento increase the percentage of inorganic material content by adding adesired amount of the removed inorganic material. It is also possible,by selecting the removal method and removal conditions, to classify intotwo groups of waste materials: one group of waste materials withdecreased inorganic material content and the other group of wastematerials with increased inorganic material content. Furthermore, theprovision of separating process 3 prevents the integral units from beingpulverized together with other units, thus forming particle board 13with very few impurities.

Fourth Exemplary Embodiment

FIG. 4 is a flowchart depicting a method for recycling refrigeratorscontaining rigid urethane foam and vacuum insulation material which hasinorganic material as the core material (the multi thermal insulationmaterial type refrigerators), and a method for producing vacuuminsulation material as a recycled article according to a fourthembodiment.

The procedural steps will be described with reference to FIG. 4.

Waste refrigerators which have been carried to a waste-treatmentfacility first undergo discriminating process 1 so as to be divided,based on the information stored in an electronic medium, into multithermal insulation material type refrigerators and single thermalinsulation material type refrigerators. In this process, the weight ofinorganic material and the weight of rigid urethane foam are also read.These pieces of information are used in inorganic material contentadjusting process 7, or could be used for recycling process management.

Next, the multi thermal insulation material type refrigerators having aglass fiber assembly as the core material undergo removing process 2 forremoving valuables such as compressors and refrigerants in the freezers,and then proceed to separating process 17 where the rigid urethane foamand the vacuum insulation material are cut out as integral units. Theseparating process prevents the integral units from being pulverizedtogether with other units, thus making the sorting operation eitherunnecessary or very simple.

After the integral units of the waste thermal insulation materialsundergo grinding operation 18, foaming gas contained in the rigidurethane foam is recovered in recovering process 5. In grindingoperation 18, the rigid urethane foam and the glass fiber assemblies areboth finely crushed, but the glass fiber assemblies are crushed morefinely because of their brittleness.

After the recovery of the foaming gas, the mixed waste materialscontaining the rigid urethane foam and the glass fiber assemblies arestored in recovery tower 61 for waste thermal insulation materials.Since the information on the inorganic material weight and rigidurethane foam weight is obtained in discriminating process 1, inrecovery tower 61 there is no need for the measurement of the percentageof inorganic material content in the waste materials recovered from themulti thermal insulation material type refrigerators.

In inorganic material content adjusting process 7, the glass fiberassemblies are sorted out by classifier 20 by making use of thedifference in grain size between the rigid urethane foam and the glassfiber assemblies. The operating conditions of classifier 20 aredetermined based on the information obtained in the discriminatingprocess. By this operation, mixed waste materials which contain rigidurethane foam and whose inorganic material content has been adjusted areobtained. The inorganic material content here is not less than 0.01% normore than 99.99%, and is adjusted in accordance with the requiredphysical properties of the recycled article. In the fourth embodiment,the appropriate percentage of inorganic material content is not lessthan 0.1% nor more than 60%, and more preferably, not less than 0.5% normore than 40%. When reused as the core material of vacuum insulationmaterial, the inorganic material functions as a modifier for the fillingperformance of waste rigid urethane foam. So the optimum amount ofinorganic material to be added is determined by the size of the surfacearea of the rigid urethane foam powder.

In the subsequent waste material processing process 9, the mixed wastematerials whose inorganic material content has been adjusted aresubjected to appropriate powdering operation 14, and after undergoingsealing process 15 for sealing the waste powder into a packaging memberunder a reduced pressure, vacuum insulation material 16 is obtained.

The inorganic material in the mixed waste materials containing rigidurethane foam and inorganic material has the effect of improving thefilling performance of the rigid urethane foam powder by being adjustedthe percentage of its content and being finely powdered.

The vacuum insulation material produced in accordance with the method ofthe fourth embodiment can have high insulation properties by minimizingthe size of pores formed by the rigid urethane foam powder. In thismanner, thermal insulation materials containing rigid urethane foam andvacuum insulation material which has inorganic material as the corematerial can be reused at high quality.

Furthermore, the provision of separating process 3 prevents the integralunits from being pulverized together with other units, thus formingvacuum insulation material 16 with very few impurities.

Fifth Exemplary Embodiment

FIG. 5 is a flowchart depicting a method for recycling refrigeratorscontaining rigid urethane foam and vacuum insulation material which hasdry silica powder as the core material (the multi thermal insulationmaterial type refrigerators), and a method for producing vacuuminsulation material as a recycled article according to a fifthembodiment.

The procedural steps will be described with reference to FIG. 5.

Waste refrigerators which have been carried to a waste-treatmentfacility first undergo discriminating process 1 so as to be divided,based on the information stored in an electronic medium, into the multithermal insulation material type refrigerators and single thermalinsulation material type refrigerators. In this process, the weight ofinorganic material and the weight of rigid urethane foam are also read.These pieces of information are used in inorganic material contentadjusting process 7, or could be used for recycling process management.

Next, the multi thermal insulation material type refrigerators havingdry silica powder as the core material undergo removing process 2 forremoving valuables such as compressors and refrigerants in the freezers,and then proceed to separating process 17 where the rigid urethane foamand the vacuum insulation material are cut out as integral units. Theseparating process prevents the integral units from being pulverizedtogether with other units, thus making the sorting operation eitherunnecessary or very simple.

As the result that the integral units of the waste thermal insulationmaterials undergo grinding operation 18, foaming gas contained in therigid urethane foam is recovered in recovering process 5. In thisgrinding operation, the rigid urethane foam is ground to fine powder,while the dry silica powder is originally smaller in size.

After the recovery of the foaming gas, the mixed waste materialscontaining rigid urethane foam and dry silica powder are stored inrecovery tower 61 for waste thermal insulation materials. Since theinformation on the inorganic material weight and rigid urethane foamweight is obtained in discriminating process 1, there is no need herefor the measurement of the percentage of inorganic material content inthe waste thermal insulation materials recovered from the multi thermalinsulation material type refrigerators.

In inorganic material content adjusting process 7, the dry silica powderis sorted out by classifier 20 by making use of the difference in grainsize between the rigid urethane foam and the dry silica powder. Theoperating conditions of classifier 20 are determined based on theinformation obtained in the discriminating process. By this operation,mixed waste materials containing rigid urethane foam whose inorganicmaterial content has been adjusted are obtained. The inorganic materialcontent here is not less than 0.01% nor more than 99.99%, and isadjusted in accordance with the required physical properties of therecycled article. In the fifth embodiment, the appropriate percentage ofinorganic material content is not less than 0.1% nor more than 60%, andmore preferably, not less than 0.5% nor more than 40%. When reused asthe core material of vacuum insulation material, the inorganic materialfunctions as an modifier for the filling performance of waste rigidurethane foam, so that the optimum amount of inorganic material to beadded is determined by the size of the surface area of the rigidurethane foam powder. Here, modifying the filling performance means thatthe powder can be filled easily or densely.

In the subsequent waste material processing process 9, the mixed wastematerials whose inorganic material content has been adjusted aresubjected to appropriate powdering operation 14, and after undergoingsealing process 15 for sealing the waste powder into a packaging memberunder a reduced pressure, vacuum insulation material 16 is obtained.

The filling performance of the rigid urethane foam powder can bemodified or improved by adjusting the percentage of dry silica contentin the mixed waste materials containing the rigid urethane foam and thedry silica. As a result, the vacuum insulation material produced inaccordance with the method of the fifth embodiment can have highinsulation properties because the size of pores formed by the rigidurethane foam powder is minimized. In this manner, thermal insulationmaterials containing rigid urethane foam and vacuum insulation materialwhich has inorganic material as the core material can be reused at highquality.

Sixth Exemplary Embodiment

FIG. 6 is a flowchart depicting a method for recycling thermalinsulation material containing rigid urethane foam and vacuum insulationmaterial which has a glass fiber assembly as the core material(hereinafter, the multi thermal insulation materials), and a method forproducing a glass fiber assembly as a recycled article according to asixth embodiment.

The procedural steps will be described with reference to FIG. 6.

Waste thermal insulation materials which have been carried to awaste-treatment facility first undergo separating process 17 where therigid urethane foam and the vacuum insulation material are cut out asintegral units. Separating process 17 prevents the integral units frombeing pulverized together with other units, thus making the sortingoperation either unnecessary or very simple.

After the integral units of the waste thermal insulation materialsundergo grinding operation 18, foaming gas contained in the thermalinsulation materials is recovered in recovering process 5.

After the recovery of the foaming gas, the mixed waste materialscontaining rigid urethane foam and inorganic material which have beendischarged from the multi thermal insulation materials are stored inrecovery tower 61 for waste thermal insulation materials. In thisprocess, the waste thermal insulation materials recovered from the multithermal insulation materials are measured for the glass content, andthis information is used in the subsequent inorganic material contentadjusting process 7.

In inorganic material content adjusting process 7, the glass fiber issorted out by air sorter 19 by making use of the difference in specificgravity between the rigid urethane foam and the inorganic material. Theoperating conditions of air sorter 19 are determined based on themeasurement results of the percentage of inorganic material content. Theinorganic material content here is not less than 0.01% nor more than99.99%, and is adjusted in accordance with the required physicalproperties of the recycled article. In the sixth embodiment, theappropriate percentage of inorganic material content is not less than95% nor more than 99.99%, and more preferably, not less than 98% normore than 99.99%. Air sorting 19 allows mixed waste materials to bemainly composed of glass fiber by sorting them until the mixed wastematerials have a maximum glass fiber content of 99.99%.

In the subsequent waste material processing process 9, the mixed wastematerials mainly composed of glass fiber are subjected to appropriatehigh-temperature melting operation 21, and then to centrifugation 22 soas to return to glass fiber assembly 23.

Seventh Exemplary Embodiment

A cross sectional view of particle board 13 as a recycled articleproduced by the processes in the first embodiment is shown in FIG. 7 asan example of a seventh embodiment. In FIG. 7, particle board 13 mainlycontains rigid urethane foam waste 24, inorganic material waste 25 whichused to be the core material of vacuum insulation material, timber chips26 and binder 27. Since being made of the waste materials which havebeen pulverized in pulverizing process 3 and then sorted out by magneticor wind force, particle board 13 contains some impurities 28. The term“particle board” indicates a board made of organic or inorganic materialin particulate or powdered form by using pressure, heat or binder. Theparticle board has only to contain the waste thermal insulationmaterials at least in part.

Eighth Exemplary Embodiment

A cross sectional view of vacuum insulation material 16 as a recycledarticle produced by the processes of the second embodiment is shown inFIG. 8 as an example of an eighth embodiment. Vacuum insulation material16 is formed of packaging member 29 containing a metal foil layer and athermoplastic polymer layer, and of a core material which is filled intopackaging member 29 as the core material and which contains finelypowdered rigid urethane foam waste 24 and glass fiber assembly waste 30that used to be the core material of vacuum insulation material. Thecore material is dried for 1 hour at 140° C., and inserted intopackaging member 29. After the pressure inside is reduced down to 13.3Pa, the opening is bonded by a heat seal so as to produce vacuuminsulation material 16. The vacuum insulation material thus obtained ischecked for thermal conductivity by using Auto-λ manufactured by EKOInstruments Co., Ltd. at an average temperature of 24° C. to find thatthe thermal conductivity is 0.0060 Kcal/m·h·°0 C. with excellentinsulation performance.

In the vacuum insulation material thus formed, the finely powdered glassfiber assembly waste adheres to the surface of the finely powderedurethane foam waste so as to improve the filling performance of thefinely powdered urethane foam waste, thus minimizing the pore size. As aresult, the vacuum insulation material shows excellent insulationperformance.

Ninth Exemplary Embodiment

A cross sectional view of particle board 13 as a recycled articleproduced by the processes in the third embodiment is shown in FIG. 9 asan example of a ninth embodiment. Particle board 13 mainly containsrigid urethane foam waste 24, inorganic material waste 25 which used tobe the core material of vacuum insulation material, timber chips 26 andbinder 27.

Since being made of the waste materials which have been cut out asintegral units of the rigid urethane foam and the vacuum insulationmaterial in separating process 3 without being pulverized together withother units, particle board 13 contains very few impurities.

Tenth Exemplary Embodiment

A cross sectional view of vacuum insulation material 16 as a recycledarticle produced by the processes of the fourth embodiment is shown inFIG. 10 as an example of a tenth embodiment. Vacuum insulation material16 is formed of packaging member 29 containing a metal foil layer and athermoplastic polymer layer, and of a core material which is filled intopackaging member 29 as the core material and which contains rigidurethane foam waste 24 and glass fiber assembly waste 30 that used to bethe core material of vacuum insulation material. The core material isdried for 1 hour at 140° C., and inserted into packaging member 29.After the pressure inside is reduced down to 13.3 Pa, the opening isbonded by a heat seal so as to produce vacuum insulation material 16.The vacuum insulation material thus obtained is checked for thermalconductivity by using Auto-λ manufactured by EKO Instruments Co., Ltd.at an average temperature of 24° C. to find that the thermalconductivity is 0.0055 Kcal/m·h·° C. with further excellent insulationperformance. In the vacuum insulation material thus formed, the finelypowdered inorganic material waste adheres to the surface of the finelypowdered urethane foam waste so as to improve the filling performance ofthe finely powdered urethane foam waste, thus minimizing the pore size.As a result, the vacuum insulation material shows excellent insulationperformance.

Since being made of the waste materials which have been cut out asintegral units of the rigid urethane foam and the vacuum insulationmaterial in separating process 3 without being pulverized together withother units, particle board 13 contains very few impurities, thusshowing more excellent insulation performance than in the eighthembodiment.

Eleventh Exemplary Embodiment

Refrigerator 31 as an example of an eleventh embodiment is shown in FIG.11. Refrigerator 31 is a multi thermal insulation material typerefrigerator provided with rigid urethane foam and vacuum insulationmaterial which has inorganic material as the core material. The outerbox of the refrigerator has control display panel 32 fixed thereon toindicate the use of vacuum insulation material in the refrigerator.

As control display panel 32, it is possible to use a SmartMedia cardwith information stored thereon, a plate with a bar code stored thereonor the like so that the information stored can be read electronically inthe discriminating process, thus efficiently changing the method forprocessing the refrigerator.

The vacuum insulation material used in the present invention is formedof a core material and a packaging member, and the core material issealed into the packaging member under a reduced pressure. To maintainvacuum in the vacuum insulation material for a long period of time, thepackaging member can contain a water absorbent and a gas absorbent suchas a physical absorbent like synthetic zeolite, active carbon, activealumina, silica gel, dawsonite or hydrotalcite, or a chemical absorbentlike an oxide or hydroxide of an alkali metal or an alkali earth metal.It is also possible to provide a process of drying the core materialbefore the vacuum sealing.

The packaging member used in the present invention can be made ofmaterial capable of blocking the core material from the outside air.Examples of such material include: thin metal plates of stainless steel,aluminum and iron; and laminate members of these thin metal plates andplastic films. The laminate member preferably has a surface protectionlayer, a gas barrier layer and a heat adhesive layer. The surfaceprotection layer can be made of polyethylene terephthalate stretch filmor polypropylene stretch film. In addition, providing nylon film outsidecan improve flexibility, thus improving bendability.

The gas barrier layer can be made of metal foil or metallized film byusing aluminum or the like. To reduce heat leak and to have moreexcellent insulating effects, the metallized film is more preferable. Itis preferable to metallize on the surface of film such as polyethyleneterephthalate film, ethylene-vinyl alcohol copolymer film, orpolyethylene naphthalate film.

The heat adhesive layer can be made of low density polyethylene film,high density polyethylene film, polypropylene film, polyacrylonitrilefilm, unstretched polyethylene terephthalate film or the like.

The inorganic material used in the present invention can be applied invarious forms such as fiber, powder, porous body and foam. The fiber canbe an inorganic material fiber such as glass wool, ceramic fiber or rockwool, and can be in any form such as non-woven fabric, textile orcotton. It is also possible to use organic binder to make the inorganicfiber an assembly. The powder can be an inorganic material powder suchas agglomerated silica power, crushed powder of foamed perlite,diatomaceous earth powder, calcium silicate powder, calcium carbonatepowder, calcium carbonate powder, clay or talc. The porous body can bean inorganic oxide aerogel such as a silica aerogel or an aluminaaerogel. It is also possible to use a mixture of two or more kinds ofthem.

The term “the percentage of inorganic material content” used in thepresent invention indicates the weight percentage of inorganic materialin the waste thermal insulation materials, and is calculated by puttingthe weight of the inorganic material in the mixed waste materialscontaining rigid urethane foam and inorganic material in the numerator,and by putting the sum of the rigid urethane foam weight and theinorganic material weight in the denominator. That is, the weight of theinorganic material divided by the sum of the rigid urethane foam weightand inorganic material weight makes the percentage of inorganic materialcontent. The inorganic material content is adjusted to be not less than0.01% nor more than 99.99% in accordance with the desired properties ofthe recycled article to be made from the waste thermal insulationmaterials. Although the appropriate percentage of inorganic materialcontent differs depending on the desired physical properties of therecycled article, when the inorganic material is regenerated as the corematerial of vacuum insulation material, it is preferably not less than0.1% nor more than 20%.

It is industrially difficult to make the inorganic material content lessthan 0.01 or more than 99.99%.

In the embodiments, one approach to the adjustment of the percentage ofinorganic material mixture is to mix the rigid urethane foam andinorganic materials recovered from multi thermal insulation materialswith the rigid urethane foam recovered from single thermal insulationmaterials in such a manner as to have a uniform percentage of inorganicmaterial content. The other approach is to remove some amounts ofinorganic material from the mixed waste materials containing rigidurethane foam and inorganic material recovered from the multi thermalinsulation materials in such a manner as to have a uniform percentage ofinorganic material content. However, these are not the only approachesapplicable for the present invention. Note that the thermal insulationmaterial containing rigid urethane foam and vacuum insulation materialhaving a glass fiber assembly as the core material is referred to as themulti thermal insulation material, whereas the thermal insulationmaterial not containing vacuum insulation material is referred to as thesingle thermal insulation material.

For the separation of the inorganic material, it is possible to useclassifying technique such as dry classification, wet classification orsieving. Gravity separation is also applicable. It is preferable toselect an appropriate approach of separation in accordance with thefeatures of the inorganic material to be used and with the properties ofthe mixed waste materials shown after the pulverizing process or theseparating process.

For the pulverization in the pulverizing process in the presentinvention, general-purpose crushers such as preshredders and one-axiscar shredders can be used. It is also possible to combine two or morekinds of crushers so that fine crushing can be performed after roughcrushing.

The term “particle board” used in the present invention indicates aboard made of organic or inorganic material in particulate or powderedform by using pressure, heat or binder. The particle board has only tocontain the waste thermal insulation materials at least in part. Thebinder can be an organic or inorganic material binder capable of bindingparticles containing waste multi materials. As the organic materialbinder, it is possible to use thermoplastic or thermosetting resin whichis generally used. Examples of the thermoplastic resin include:polypropylene, polyethylene, polystyrene, astyrene-butadiene-acrylonitrile copolymer, polyamide, polycarbonate,polyacetal and polyethylene terephthalate. Examples of the thermosettingresin include: phenol, urea, melanine and urethane. These can be usedsolely or in a mixture of two or more kinds. As the inorganic binder, itis possible to use an inorganic material that functions as a bindingmaterial such as water glass, colloidal silica, silica sol or aluminasol.

The refrigerator according to the present invention is applicable notonly as a refrigerator used between −30° C. and normal temperature whichis the normal operating temperature range, but also as a refrigeratormaking use of heating and cooling in a wider temperature range, such asa vending machine. The refrigerator also can be a gas refrigerator aswell as an electric refrigerator.

As the discriminating means used in the present invention, it ispossible (1) to provide a control display panel indicating that therefrigerator has vacuum insulation material or (2) to provide a bar cordindicating that the refrigerator contains vacuum insulation material,the weights of the core material and rigid urethane foam so as toperform automatic discrimination; however, the present invention is notlimited to these means. As shown in FIG. 11, the discriminating means ispreferably displayed or recorded on the outer box of the refrigerator,and more preferably, on the rear surface. The reason for this is thatthe side surfaces or the front part of the top surface may have stickerspasted thereon while being used in ordinary households, and consequentlythe sensor function for discrimination may be damaged. On the otherhand, providing the discriminating means inside the refrigeratorrequires an internal search sensor, thus complicating the discriminatingprocess. In contrast, the rear surface of the refrigerator is usually inthe vicinity of a wall, thus maintaining its original condition andhaving few chances of damaging the sensor function.

The glass fiber assembly used in the present invention is a fibrousaggregate composed of glass compositions such as A-glass, C-glass andE-glass, whether it is short fiber or long fiber, or whether it uses abinder or not. In addition, the glass fiber assembly can be used in theform of raw cotton or mat. The short fiber made by centrifugation isparticularly preferable because it has a track record as a recycled rawmaterial, and is also inexpensive. In manufacturing the vacuuminsulation material, it is preferable to mold it with a binder becauseof the easier insertion into the packaging member, excellent sizestability and other advantages.

INDUSTRIAL APPLICABILITY

In order to contribute to the recycling of thermal insulation materialcontaining rigid urethane foam and vacuum insulation material, thepresent invention provides a method for recycling thermal insulationmaterial in such a manner that mixed waste materials can have a uniformquality and be reused at high quality, and also provides a recycledarticle. The present invention also provides a refrigerator that enablesmixed waste materials to have a uniform quality and to be reused at highquality in order to contribute to the recycling of thermal insulationmaterial containing rigid urethane foam and vacuum insulation material.Thus, the present invention can improve the rate of recycling of wasterefrigerators, thus contributing to the recycling, and can also providean energy-efficient and environment-friendly refrigerator. Therefore,the present invention has industrial significance.

1. A method for recycling thermal insulation material which is formed ofvacuum insulation material having inorganic material as a core materialand of rigid urethane foam, the method comprising: a step of pulverizingthe thermal insulation material containing the inorganic material andthe rigid urethane foam; and an inorganic material content adjustingstep of adjusting a percentage of inorganic material content in mixedmaterial consisting of the thermal insulation material pulverized, theinorganic material content adjusting step including a step of measuringthe percentage of inorganic material content in the mixed materialpulverized.
 2. The method for recycling the thermal insulation materialaccording to claim 1 further comprising: a step of pulverizing secondthermal insulation material exclusively consisting of rigid urethanefoam, wherein the inorganic material content adjusting step is a step ofmixing the pulverized thermal insulation material containing the vacuuminsulation material with the second thermal insulation materialpulverized, based on a measured percentage of inorganic materialcontent, thereby obtaining the mixed material with a prescribedpercentage value of inorganic material content.
 3. The method forrecycling the thermal insulation material according to claim 1, whereinthe inorganic material content adjusting step is a step of obtaining themixed material with a prescribed percentage value of inorganic materialcontent by sorting out and removing the inorganic material contained inthe pulverized thermal insulation material, based on the measuredpercentage of inorganic material content.
 4. The method for recyclingthe thermal insulation material according to claim 3, wherein thesorting operation is air sorting which makes use of difference inspecific gravity between the inorganic material and the rigid urethanefoam.
 5. The method for recycling the thermal insulation materialaccording to claim 3, wherein the sorting operation is classificationwhich makes use of difference in grain size between the pulverizedinorganic material and the pulverized rigid urethane foam.
 6. The methodfor recycling the thermal insulation material according to claim 1further comprising: a separating step of cutting out the vacuuminsulation material and the rigid urethane foam as an integral unit froma main body of a refrigerator.
 7. The method for recycling the thermalinsulation material according to claim 1 further comprising: a wastematerial processing step of processing the mixed material obtained inthe inorganic material content adjusting step into a recyclable form. 8.The method for recycling the thermal insulation material according toclaim 7, wherein the waste material processing step is a step of moldinga particle board, and includes an operation to pressurize the mixedmaterial.
 9. The method for recycling the thermal insulation materialaccording to claim 7, wherein the waste material processing step is astep of producing vacuum insulation material, and includes: an operationto powder the mixed material; and a step of sealing the powder thusobtained into a coating member under a reduced pressure.
 10. The methodfor recycling the thermal insulation material according to claim 1further comprising: a discriminating step of reading an inorganicmaterial weight value and a rigid urethane foam weight value from adiscriminating means owned by a refrigerator, wherein the inorganicmaterial content adjusting step makes use of the inorganic materialweight value and the rigid urethane foam weight value in order to adjustthe percentage of inorganic material content in the mixed material. 11.The method for recycling the thermal insulation material according toclaim 1, wherein the inorganic material is a glass fiber assembly.
 12. Arecycled article made by recycling thermal insulation material which isformed of vacuum insulation material having inorganic material as a corematerial and of rigid urethane foam, wherein mixed material which isformed of the vacuum insulation material and the rigid urethane foam hasan inorganic material content that is adjusted to be not less than 0.01%nor more than 99.99%.
 13. The recycled article according to claim 12,wherein the article is a particle board which is made by pressurizingand molding the mixed material.
 14. The recycled article according toclaim 12, wherein the article is vacuum insulation material which ismade by sealing a powder consisting of the mixed material into a coatingmember under a reduced pressure.
 15. The recycled article according toclaim 14, wherein the powder contains inorganic material of not lessthan 0.1% nor more than 20%.
 16. A refrigerator containing thermalinsulation material which is formed of vacuum insulation material havinginorganic material as a core material and of rigid urethane foam, therefrigerator comprising: a discriminating means, the discriminatingmeans recording information that the thermal insulation materialcontains the vacuum insulation material, a weight value of the inorganicmaterial and a weight value of the rigid urethane foam.
 17. (canceled)18. The refrigerator according to claim 16, wherein the discriminatingmeans is provided on a surface of an outer box of the refrigerator. 19.The refrigerator according to claim 16, wherein the discriminating meansis a medium capable of electronic reading.